Serra da Canastra National Park: Influence of forest fires on the RUSLE C factor and its impact on water erosion

Abstract

The adverse impacts of soil degradation and nutrient loss resulting from water erosion are significant environmental concerns that have profound implications for both water quality and biodiversity. This study aims to evaluate the impact of forest fires on soil loss through water erosion in the Serra da Canastra National Park, in Minas Gerais state, Brazil. Using the Revised Universal Soil Loss Equation (RUSLE), which considers rainfall erosivity, soil erodibility, slope length and slope and vegetation cover, the C factor (vegetation cover) values were obtained from data from literature and methods based on the Normalized Differential Vegetation Index (NDVI). Validation was carried out using data on total sediment, water flow and daily runoff from the hydrosedimentological station and the InVEST software. The results highlight the significant impact of wildfires on soil loss through water erosion and indicate that areas recently affected by wildfires, especially on steep slopes and with more erodible soils, are subject to the highest rates of soil loss. Soil loss rates varied from 0.75 to 12.55 Mg ha-1 yr-1, in part due to the different ways of obtaining factor C. The research emphasizes the need to conserve vegetation cover to prevent soil erosion, particularly in regions impacted by forest fires. This study offers valuable insights that can contribute to enhancing the sustainable environmental management of the Serra da Canastra National Park.